crypto-analysis
Breaks cryptographic systems and decrypts ciphertext. Use when working with RSA, AES, XOR, classical ciphers, hash functions, or when challenge involves encryption, decryption, keys, or mathematical crypto attacks.
Packaged view
This page reorganizes the original catalog entry around fit, installability, and workflow context first. The original raw source lives below.
Install command
npx @skill-hub/cli install benchflow-ai-skillsbench-crypto-analysis
Repository
Skill path: registry/terminal_bench_2.0/full_batch_reviewed/terminal_bench_2_0_feal-linear-cryptanalysis/environment/skills/crypto-analysis
Breaks cryptographic systems and decrypts ciphertext. Use when working with RSA, AES, XOR, classical ciphers, hash functions, or when challenge involves encryption, decryption, keys, or mathematical crypto attacks.
Open repositoryBest for
Primary workflow: Ship Full Stack.
Technical facets: Full Stack.
Target audience: everyone.
License: Unknown.
Original source
Catalog source: SkillHub Club.
Repository owner: benchflow-ai.
This is still a mirrored public skill entry. Review the repository before installing into production workflows.
What it helps with
- Install crypto-analysis into Claude Code, Codex CLI, Gemini CLI, or OpenCode workflows
- Review https://github.com/benchflow-ai/SkillsBench before adding crypto-analysis to shared team environments
- Use crypto-analysis for development workflows
Works across
Favorites: 0.
Sub-skills: 0.
Aggregator: No.
Original source / Raw SKILL.md
--- name: crypto-analysis description: Breaks cryptographic systems and decrypts ciphertext. Use when working with RSA, AES, XOR, classical ciphers, hash functions, or when challenge involves encryption, decryption, keys, or mathematical crypto attacks. allowed-tools: Bash, Read, Write, Grep, Glob --- # Crypto Analysis Skill ## Quick Workflow ``` Progress: - [ ] Try Ciphey auto-decrypt first - [ ] Identify crypto type (RSA/AES/XOR/classical) - [ ] Check for known weaknesses - [ ] Implement attack - [ ] Decrypt flag ``` ## Step 1: Auto-Decrypt (Try First!) ```bash ciphey -t "ENCODED_TEXT" # Auto-detects and decrypts ciphey -f encrypted.txt # From file ``` ## Step 2: Identify Crypto Type | Pattern | Crypto Type | Reference | |---------|-------------|-----------| | `n, e, c` variables | RSA | [reference/rsa-attacks.md](reference/rsa-attacks.md) | | 16/32 byte key, IV | AES | [reference/aes-attacks.md](reference/aes-attacks.md) | | XOR operations | XOR/Stream | [reference/classical.md](reference/classical.md) | | Polynomial mod | Lattice | [reference/lattice.md](reference/lattice.md) | ## RSA Attack Decision Tree ``` ├── e small (≤5)? → Direct eth root ├── e very large? → Wiener's Attack ├── Multiple n,e,c? → Hastad's Broadcast ├── Same n, diff e? → Common Modulus ├── GCD(n1,n2) > 1? → Common Factor ├── p ≈ q? → Fermat Factorization ├── dp/dq leaked? → Partial Key Recovery └── Default → FactorDB / yafu ``` **Full implementations**: [reference/rsa-attacks.md](reference/rsa-attacks.md) ## Quick Commands ```bash # Auto-decrypt ciphey -t "text" # XOR analysis xortool encrypted.bin xortool -c 20 encrypted.bin # Expect spaces # Factor large n yafu "factor(<n>)" # RSA tool python3 RsaCtfTool.py -n <n> -e <e> --uncipher <c> # Lattice (SageMath) sage solve.sage ``` ## Reference Files - **[RSA Attacks](reference/rsa-attacks.md)**: Small e, Wiener, Hastad, Common Modulus, Fermat, FactorDB - **[AES Attacks](reference/aes-attacks.md)**: ECB detection, CBC flip, Padding Oracle - **[Classical/XOR](reference/classical.md)**: Ciphey, xortool, frequency analysis, Vigenère - **[Lattice](reference/lattice.md)**: Coppersmith, LLL, HNP